NAME

tz − SCSI magnetic tape interface

SYNOPSIS

Digital AlphaServer 8200 and Digital AlphaServer 8400 Qlogic ISP1020:
 bus tlsb0 at nexus? 
 bus tiop0 at tlsb0 vector tioperror
 bus isp0 at ∗ vector ispintr
 controller scsi0 at ∗ vector scsiintr
 controller scsi1 at ∗ vector scsiintr Digital AlphaServer 8200 and Digital AlphaServer 8400 DEC KZMSA:
 bus tlsb0 at nexus?
 bus tiop0 at tlsb0 vector tioperror
 bus xmi0 at tiop? vector xmierror
 bus xza0 at xmi?
 controller scsi0 at ∗ vector scsiintr
 controller scsi1 at ∗ vector scsiintr  DEC 7000/10000 DEC KZMSA:
 bus lsb0 at nexus?
 bus iop0 at lsb0 vector ioperror
 bus xmi0 at iop0 vector xmierror
 bus xza0 at xmi?
 controller scsi0 at ∗ vector scsiintr
 controller scsi1 at ∗ vector scsiintr  DEC 4000 DEC SIOP:
 bus ibus0 at nexus?
 bus lbus0 at ibus0
 bus siop0 at lbus0 slot 0 vector siopcointr
 controller scsi0 at ∗ vector scsiintr  DEC 3000 NCR ASC:
 bus tc0 at nexus?
 bus tcds0 at ∗ vector tcdsintr
 controller scsi0 at ∗ vector scsiintr
 controller scsi1 at ∗ vector scsiintr  DEC 3000 DEC KZTSA:
 bus tc0 at nexus?
 bus tza0 at ∗ vector kztsaintr
 controller scsi0 at ∗ vector scsiintr  DEC PCI bus DEC KZPSA:
 bus pci0 at ∗
 bus pza0 at pci? vector pzaintr
 controller scsi0 at ∗ vector scsiintr  DEC PCI bus NCR 810:
 bus pci0 at ∗
 bus psiop at pci? vector psiopintr
 controller scsi0 at ∗ vector scsiintr  DEC PCI bus Qlogic ISP1020:
 bus pci0 at ∗
 bus isp0 at ∗ vector ispintr
 controller scsi0 at ∗ vector scsiintr DEC EISA bus Adaptec 1740:
 bus eisa0 at ∗
 bus aha0 at ∗ vector ahaintr
 controller scsi0 at ∗ vector scsiintr

DESCRIPTION

The Small Computer System Interface (SCSI) tape driver provides a standard tape drive interface as described in mtio(7).  This is the tape driver for any Digital SCSI tape device.  Facilities are provided to allow the addition of third-party SCSI tape drives to the system. Refer to the ddr_config(8) and ddr.dbase(4) reference pages for instructions. 

For reads from Beginning of Media (BOM), the density of the tape is obtained from the drive.  Autodensity selection is then used for all read operations.  This means that reads are performed in the density of the tape. 

For writes from BOM, the density, compression, and blocking factor of the tape are set.  The tape is written in the density, compression, and blocking factor that the user has selected by specifying one of the following device special files:  rmt?a; rmt?l; rmt?m; or rmt?h. If the tape is not at BOM, the same density, compression, and blocking factors are used which the rest of the tape has been written with. 

The following are the default densities for specific SCSI tape drives:

    TZ30: Single-density drive.
rmt?a 6666 BPI
rmt?l 6666 BPI
rmt?m 6666 BPI
rmt?h 6666 BPI
    TLZ04: Single-density drive.
rmt?a 61000 BPI
rmt?l 61000 BPI
rmt?m 61000 BPI
rmt?h 61000 BPI
    TLZ06: Single-density drive, compaction support.
           Read/write TLZ04 format.
rmt?a 61000 BPI
rmt?l 61000 BPI
rmt?m 61000 BPI, compaction turned on.
rmt?h 61000 BPI, compaction turned on.
    TLZ07: Single-density drive, compaction support.
           Read/write TLZ04 and TLZ06 format.
rmt?a 61000 BPI
rmt?l 61000 BPI
rmt?m 61000 BPI, compaction turned on.
rmt?h 61000 BPI, compaction turned on.
    TSZ07: Dual-density drive.
rmt?a 6250 BPI
rmt?l 1600 BPI
rmt?m 1600 BPI
rmt?h 6250 BPI
    TKZ08: Single-density drive (Exabyte 8200).
rmt?a 54000 BPI
rmt?l 54000 BPI
rmt?m 54000 BPI
rmt?h 54000 BPI
    TKZ09: Dual-format drive, supports Exabyte 8200 and 8500
    formats.
rmt?a 54000 BPI (8200 format)
rmt?l 54000 BPI (8200 format)
rmt?m 45434 BPI (8500 format)
rmt?h 45434 BPI (8500 format)
    TZK10: QIC-format drive.
 See description that follows.
    TZK11: QIC-format drive.
See description that follows.
    TZK20: Single-density drive (Tandberg TDC 3700 QIC-3210(MC)).
        rmt?a 61040 BPI
        rmt?l 61040 BPI
        rmt?m 61040 BPI
        rmt?h 61040 BPI

The following table lists the tape compatibility for CompactTape media and the TZ85, TZ86, TZ87, TZ88, and TZ89 tape drives. 

The following tables provide information for the TZ85, TZ86, TZ87, TZ88, and TZ89 tape drives. All of these tape drives support variable block size.  Note that in the capacity column, a number followed by an asterisk (∗) assumes a 2:1 compression ratio. The actual compression ratio may vary depending on the type of data being compressed.  TZ85 Tape Drive Supported Formats

TZ86 Tape Drive Supported Formats

TZ87 Tape Drive Supported Formats

TZ88 Tape Drive Supported Formats

TZ89 Tape Drive Supported Formats

The following formats are supported for the TZK10 QIC-format tape drive: QIC-24 (read-only) 512-byte block size; QIC-120 and QIC-150 (read/write) 512-byte block size; and QIC-320 (read/write) variable block size.  With QIC-format tapes, except QIC-320 and QIC-525, all read and write operations must be in multiples of the block size because record boundaries are not preserved.  Use the following device special file names to select QIC densities:

The following formats are supported for the TZK11 QIC-format tape drive: QIC-24 (read only) 512-byte block size; QIC-120 and QIC-150 (read/write) 512-byte block size; and QIC-320/525/1Gig/2Gig (read/write) variable block size.  With QIC-format 24/120/150 tapes, all read and write operations must be in multiples of the block size because record boundaries are not preserved.  Use the following device special file names to select QIC densities:

The TZK11 tape drive uses autodensity select feature of the drive. The 2 Gig density can only be written on a 2 Gig cartridge.  The 1 Gig density can only be written on a 1 Gig cartridge.  The 320/525 cartridge can be used to write 120/150/320/525 densities. With all fixed-block tape devices, when you use the dd command to transfer a file to tape you must use padding to complete a block by specifying the conv=sync option.  For example, the following two dd commands use the conv=sync option to transfer the /etc/motd file with a size of approximately 400 bytes to the QIC-format tape drives:

dd if=/etc/motd of=/dev/rmt0m bs=10k conv=sync

dd if=/etc/motd of=/dev/rmt0l bs=512 conv=sync

The TZ30 and TLZ04 tape drives require a SCSI Bus Device Reset (BDR) be sent to these devices when scanning the SCSI bus during the boot sequence.  An attribute has been added to the TZ30 and TLZ04 section of the /etc/ddr.dbase text database file which triggers a BDR to these devices at boot time.  This attribute looks like:

    ATTRIBUTE:
        AttributeName = "BDRatBoot"
        Length        = 1
        UBYTE[0] = 1

The data field of 1 also tells the driver not to continue scanning LUNs for this target when this attribute is found. 

Tape Support

Refer to the Software Product Description (SPD) for information on the specific tape devices that are supported.  Refer to the Systems and Options Catalog (SOC) for information on which devices are supported on the various system platforms. 

EXAMPLES

The following example shows the configuration specification that you might have for a DEC 3000 Model 500 system with a PMAZC controller in slot 0 and KZTSA devices in slots 1 and 2:

bus tc0 at nexus?
bus tcds0 at tc0 slot 6 vector tcdsintr         # onboard scsi
bus tcds1 at tc0 slot 0 vector tcdsintr         # PMAZC in tc slot 0
bus tza0 at tc0 slot 1 vector kztsaintr         # KZTSA in tc slot 1
bus tza1 at tc0 slot 2 vector kztsaintr         # KZTSA in tc slot 2
controller scsi0 at tcds0 slot 0 vector scsiintr # Internal port
controller scsi1 at tcds0 slot 1 vector scsiintr # External port
controller scsi2 at tcds1 slot 0 vector scsiintr # A port
controller scsi3 at tcds1 slot 1 vector scsiintr # B port
controller scsi4 at tza0 slot 0 vector scsiintr
controller scsi5 at tza1 slot 0 vector scsiintr

ERRORS

All diagnostic messages are sent to the error logger subsystem. 

FILES

/dev/rmt???, /dev/nrmt???

RELATED INFORMATION

ddr.dbase(4), ddr_config(8), mtio(7), RAID(7), SCSI(7), MAKEDEV(8), uerf(8), tapex(8)